The Automatic Dependent Surveillance-Broadcast (ADS-B) is a surveillance technology that becomes mandatory in many airspaces. It improves safety, increases efficiency and reduces air traffic congestion by broadcasting aircraft navigation data. Yet, ADS-B is vulnerable to spoofing attacks as it lacks mechanisms to ensure the integrity and authenticity of the data being supplied. None of the existing cryptographic solutions fully meet the backward compatibility and bandwidth preservation requirements of the standard. Hence, we propose the Compatible Authenticated Bandwidth-efficient Broadcast protocol for ADS-B (CABBA), an improved approach that integrates TESLA, phase-overlay modulation techniques and certificate-based PKI. As a result, entity authentication, data origin authentication, and data integrity are the security services that CABBA offers. To assess compliance with the standard, we designed an SDR-based implementation of CABBA and performed backward compatibility tests on commercial and general aviation (GA) ADS-B in receivers. Besides, we calculated the 1090ES band's activity factor and analyzed the channel occupancy rate according to ITU-R SM.2256-1 recommendation. Also, we performed a bit error rate analysis of CABBA messages. The results suggest that CABBA is backward compatible, does not incur significant communication overhead, and has an error rate that is acceptable for Eb/No values above 14 dB.

翻译：自动相关监视广播（ADS-B）是一种监视技术，已在多个空域成为强制要求。它通过广播飞机导航数据，提高了安全性、效率并减少了空中交通拥堵。然而，由于缺乏确保数据完整性和真实性的机制，ADS-B容易遭受伪造攻击。现有加密方案均未能完全满足该标准对向后兼容性和带宽节省的要求。为此，我们提出了一种面向ADS-B的兼容认证高效带宽广播协议（CABBA），该改进方案集成了TESLA、相位叠加调制技术及基于证书的公钥基础设施（PKI）。因此，CABBA提供了实体认证、数据起源认证和数据完整性等安全服务。为评估其是否符合标准，我们设计了一套基于软件无线电（SDR）的CABBA实现，并在商用和通用航空（GA）ADS-B接收机上进行了向后兼容性测试。此外，根据ITU-R SM.2256-1建议书，我们计算了1090ES频段的活动因子并分析了信道占用率。同时，还对CABBA消息进行了误码率分析。结果表明：CABBA具备向后兼容性，不会产生显著通信开销，且在Eb/No值高于14 dB时误码率可接受。